Michigan lawmakers reviewing the lead contamination of Flint's drinking water supply will turn to proposing recommendations, including changes to the Midwestern U.S. state's contentious emergency manager law, after two months of investigative hearings concluded Tuesday.

The Republican chairman of a special legislative committee said it likely would urge revisions to the law, though he declined to elaborate. The committee wrapped up without calling Governor Rick Snyder and some other key figures, including Flint's emergency managers, to testify.

Senator Jim Stamas of Midland said Michigan and local governments must do better at financing upgrades to aging drinking water and sewer systems across the state. In Flint, the city’s 100,000 residents are using faucet filters and bottled water while living under a months-long emergency.

A construction group told the panel Tuesday that the drinking water infrastructure statewide required additional spending of at least $284 million to $563 million a year.

Michigan's 2012 emergency management law, which the GOP-led Legislature quickly approved after voters repealed a 2011 version, lets the state exert near-total control over distressed cities and school districts under certain circumstances. It was blamed as a factor in the Flint crisis by a task force appointed by Snyder, who supports the law but has acknowledged it failed Flint.

The contamination occurred when the city, which was under emergency management at the time, switched in 2014 from the metropolitan Detroit utility system to a temporary water source, the Flint River, until it could connect to the new pipeline. State environmental regulators mistakenly told the city not to add a chemical to prevent lead from leaching out of old pipes. State emergency managers later came under scrutiny for blocking a switch back for financial reasons.

Over Democrats' objections, majority Republicans on the committee did not seek testimony from the four emergency managers who led Flint from 2011 to 2015, Snyder or former Department of Environmental Quality Director Dan Wyant, who resigned in December.

The panel instead entered the testimony that the Republican governor, former emergency manager Darnell Earley and other officials gave before Congress into its record.

“We've seen that the investigations are still ongoing for accountability, but with the amount of information this committee has received, I think the Flint residents deserve the opportunity for solutions,” Stamas said.